Add a mention of create-dev-env.sh

doc/development.md

@@ -31,6 +31,14 @@ Check out the course data directories that you want to work with into the
 
     rake resetdb
 
+## Installing
+
+To create your development environment, run the shell script in the root of
+the repo:
+
+    create-dev-env.sh
+
+
 ## Starting development servers
 
 Both the LMS and Studio can be started using the following shortcut tasks